1. Field of the Invention (Technical Field)
The present invention relates to rims for spoked wheels, and particularly to a sealing apparatus for use on such a rim.
2. Background Art
Vehicle wheels are sometimes spoked, that is there are spokes extending from the wheel rim to its hub. Wheeled spokes are less common on most vehicles than formerly, but are still popular on bicycles and motorcycles.
The rim involved is usually what is called a punched rim, i.e. featuring depressions for receiving and orienting the spoke nipples. This so-called punched hole thus ensures that the space formed between the rim and the tire disposed thereon is open and thus not air-tight. For this reason a tube is usually employed with such a spoke wheel. This known spoke wheel with a tube has a number of drawbacks.
Usually fitted between the rim bed and tube is a rim band designed to prevent damage of the tube at the spoke nipples, the combination of tire, tube, rim band and rim thus resulting in a high mass materializing for the spoke wheel formed as such. This in turn results in a high rotational moment of inertia of the spoke wheel formed as such, because of the radially outlying mass concentration, as viewed from the wheel hub, to the detriment of the handling agility of a motorcycle fitted with such a spoke wheel, for example, when intentionally changing directions. On top of this, the tube is also susceptible to damage in the form of snake bites, i.e. two holes materializing in the tube on bottoming, for instance after a jump with an off-road bike and subsequent landing in which the tube is squashed against the rim bed, resulting in two holes. Also needing to be provided on such a spoke wheel with a tube is a so-called tire holder on the rim which has the task of preventing the tire twisting out of place relative to the rim. This is because twisting of the tire is often accompanied with the problem of the twisting tire “entraining” the tube and thus the valve fitted to the tube, forcing it through the spoked rim, shearing it off.
To get around these problems tubeless tires are also already known, necessitating specially formed rims which, except for a hole for fitting the valve, comprise no opening in the rim bed. This results in the spokes also needing to be manufactured integrally with the rim bed on such tubeless rims, for instance as a cast rim which in turn are heavy and which because of the manufacture are also prone to fracture during casting and thus unsuitable for high loading.
Also to avoid these problems, attempts have already been made to create spoke wheels with tubeless tires. Examples of previous endeavors in the field are found in the following publications: Japanese patent disclosure No. JP 09002005; German patent disclosure No. DE AS 1002210; European Patent Office patent disclosure No. EP 0 615 865 A1; and USA patent disclosure U.S. Pat. No. 4,824,177.
Known also are spoke wheels with tubeless tires which attempt to do away with a sealing device in the region of the rim bed. Examples of prior publications in this field are: European Patent Office patent disclosure No. EP 0 962 338 A1, and Japanese patent disclosure No. JP 61054302.
When a tire is to be fitted to a wheel configured as such, there is no preventing the tire coming into contact with the rim band on fitting. This contact of the rim band with the tire causes the rim band to slip out of place on the rim, thus resulting in leakage locations between rim band and rim even before the wheel is inflated. The rim band needs to be reseated, but even this is no assurance of remedying the leakage locations, so that in practice the procedure is to stick the rim band to the rim. When removing the fitted tire, the leakage problem between rim band and rim is repeated, due to the tire again coming into contact with the rim band, displacing it, despite the stick. When then a new tire is mounted, the leakage problem can no longer be eliminated even when re-sticking the rim band to the rim.
Publications relating to the foregoing include the following: European Patent Office patent disclosure No. EP 06 16 911 A2; USA patent disclosure U.S. Pat. No. 3,335,778; German patent disclosure No. DE 203 16 995 U1; German patent disclosure No. DE 38 78 397 T2; and German patent disclosure No. DE 298 03 256 U1.
Against the foregoing background, the present invention was developed.